A pressure test equipment and method for a thin-walled double-cavity common bottom structure tank

Abstract

The present invention provides a pressure test equipment and method for a thin-walled double-cavity common bottom structure tank, the test equipment includes a pressure measuring device and a filling pipeline; the pressure measuring device includes an upper tank front end pressure measuring device for measuring the highest point pressure of the upper tank, an upper tank rear end pressure measuring device for measuring the lowest point pressure of the upper tank, a lower tank front end pressure measuring device for measuring the highest point pressure of the lower tank, and a lower tank rear end pressure measuring device for measuring the lowest point pressure of the lower tank; the filling pipeline is divided into two routes, one route is connected to the filling port of the upper tank of the tank, and the pipeline of the route is provided with an upper tank filling and discharge control valve; the other route is connected to the filling port of the lower tank, and the pipeline of the route is provided with a lower tank filling and discharge control valve. The present invention realizes the pressure test of the common bottom structure tank by coordinating the upper and lower tanks in steps, thereby ensuring the safety of the common bottom tank test.

Description

Technical Field

[0001] The invention belongs to the technical field of tank testing, and in particular relates to pressure test equipment and method for a tank with a thin-wall double-cavity common bottom structure. Background Art

[0002] After the launch vehicle fuel tank is assembled and welded, its manufacturing quality must be fully evaluated through a pressure test. Traditional tanks are generally single-tank structures, and the test medium is directly filled into the tank for testing. The 5-meter diameter thin-walled common bottom tank is the first split structure of this size in China. The tank is separated into two upper and lower sub-tanks by a common bottom. The common bottom is composed of two thin-walled spherical tank bottoms stacked together, and the middle interlayer is filled with insulation material. Due to this special structure, the deformation of the common bottom caused by the pressure change of the upper and lower sub-tanks will lead to the redistribution of the pressure between the upper and lower sub-tanks, and then cause the mutual influence of the pressure between the upper and lower tanks. At the same time, the special thin-walled sandwich structure of the common bottom also determines that the common bottom itself is not allowed to withstand overload or negative pressure, so as to avoid damage to the double thin walls and interlayer of the common bottom.

[0003] The pressure test process can be divided into seven stages: pre-test preparation, filling, pressurization and pressure maintenance, pressure relief, medium release, post-test processing, and weld inspection. At present, the pressure test of a single-tank structure tank is carried out by placing the tank upright on the test base, filling or inflating the pipeline from the flange connection on the bottom rear side of the tank, and performing the test process of pressurization and pressure maintenance through the test bench control.

[0004] The existing storage tanks are all single-box structures, which do not involve the coordination problem of mutual deformation between the upper and lower boxes of the split storage tank. Therefore, the existing technical solutions and process methods cannot realize the pressure test of the split common bottom storage tank. Summary of the invention

[0005] In view of this, the present invention aims to propose a pressure test equipment and a test method for a thin-walled double-cavity common bottom structure tank. The present invention aims at the pressure test demand of a split-type special structure of a large-diameter (can be used for a diameter of 5 meters) thin-walled double-cavity common bottom tank. The present invention designs a set of safe and reliable process-based technical solutions, which realizes the pressure test of the common bottom structure tank by coordinating the upper and lower tanks in steps, thereby ensuring the safety of the common bottom tank test.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] A pressure test equipment for a thin-walled double-cavity common bottom structure tank, comprising a pressure measuring device and a filling pipeline;

[0008] The pressure measuring device comprises an upper tank front end pressure measuring device for measuring the pressure at the highest point of the upper tank, an upper tank rear end pressure measuring device for measuring the pressure at the lowest point of the upper tank, a lower tank front end pressure measuring device for measuring the pressure at the highest point of the lower tank, and a lower tank rear end pressure measuring device for measuring the pressure at the lowest point of the lower tank;

[0009] The filling pipeline is divided into two paths, one of which is connected to the filling port of the upper tank of the storage tank, and the pipeline of the path is provided with an upper tank filling and discharge control valve; the other path is connected to the filling port of the lower tank of the storage tank, and the pipeline of the path is provided with a lower tank filling and discharge control valve;

[0010] It also includes an upper box exhaust / air replenishing device connected to the top of the upper box of the storage box and a lower box exhaust / air replenishing device communicated with the lower box of the storage box.

[0011] The other end of the filling pipeline is connected to a device that can be filled with medium and pressurized. The equipment in the prior art can be used as long as it can achieve filling, pressurization, discharge, and pressure relief. It is also possible to use equipment that can achieve their respective functions and connect them to the filling pipeline respectively. It is also possible to use an integrated set of equipment to achieve several functions at the same time. For example, a 5M-level tank volume calibration equipment disclosed in Chinese patent CN201510064006 can directly connect the filling pipeline of this application to the tank hydraulic volume calibration equipment in the application.

[0012] Further, the filling port of the upper tank is located at the bottom end of the upper tank side of the storage tank, and the upper tank exhaust / air replenishing device is located at the top of the upper tank of the storage tank; the filling port of the lower tank is located at the lower end of the lower tank of the storage tank;

[0013] The upper box front end pressure measuring device is arranged at the top of the upper box of the storage tank, and the upper box rear end pressure measuring device is arranged at the bottom of the upper box of the storage tank; the lower box rear end pressure measuring device is arranged at the bottom of the lower box of the storage tank.

[0014] Furthermore, it also includes an exhaust / air supply pipe that can extend to the top of the lower box of the storage tank; the lower box front end pressure measuring device and the lower box exhaust / air supply device are arranged on the exhaust / air supply pipe.

[0015] Furthermore, it also includes an upper tank emergency discharge device and a lower tank emergency discharge device connected to the top of the tank; the lower tank emergency discharge device is connected to the exhaust / air supply pipe;

[0016] By setting pressure measurement monitoring points at the front and rear ends of the upper and lower tanks of the common bottom tank, the highest and lowest pressures of the upper and lower tanks are monitored in real time. In order to prevent overpressure of the tank, emergency discharge devices are respectively set on the upper and lower tanks, which are associated with the pressure measurement devices at the highest points of the upper and lower tanks. When the pressure exceeds the upper limit of the pressure setting, the emergency discharge device discharges. The emergency discharge device is associated with the pressure measurement devices at the highest points of the upper and lower tanks. The existing control system can be used to realize automatic control, or the operator can observe the value of the pressure measurement device and manually start the emergency discharge device.

[0017] An upper tank filling zero level device and a lower tank filling zero level device are respectively provided on the pipelines connecting the filling pipeline with the upper tank and the lower tank of the storage tank;

[0018] Also included is a point level sensor connected to the top of the tank.

[0019] The filling and discharging process of the upper and lower tanks is controlled by setting two regulating stop valves on the filling pipeline. In order to determine the filling starting point, a filling zero level device (i.e., zero level sensor) is set before the test medium flows into the tank. The trigger point of the sensor is used as the filling starting point to start recording the medium flowing into the tank. The filling end point of the upper tank is set at the top of the tank. After the sensor is triggered, the filling of the upper tank stops. Due to the special structure of the lower tank, the filling end point is set when the test medium flows out of the exhaust / air supply pipe. The leakage back process is a filling pseudo process. When the zero level sensor is triggered, the leakage back stops.

[0020] Further, the upper box front end pressure measuring device, the upper box rear end pressure measuring device, the lower box front end pressure measuring device, and the lower box rear end pressure measuring device are all pressure measuring sensors;

[0021] The upper box exhaust / air supply device and the lower box exhaust / air supply device are exhaust / air supply valves.

[0022] By respectively arranging exhaust / air-supplement devices on the upper and lower boxes, and associating them with the pressure measuring devices at the highest points of the upper and lower boxes, the exhaust of gas in the box during the filling process and the timely air replenishment in the box during the leakage of the medium can be achieved. The upper box exhaust and air-supplement device is arranged at the top of the tank, and the lower box exhaust and air-supplement device is arranged at the outlet end of the lower box exhaust and air-supplement pipe. During the filling process, the exhaust / air-supplement device is in an open state to discharge the gas in the box in real time, and is closed after the filling is completed. When the tank completes the pressure test and the pressure value displayed by the pressure measuring device at the highest point of the upper and lower boxes is close to 0, the exhaust / air-supplement device is opened to achieve the connection between the upper and lower boxes and the atmospheric environment.

[0023] In order to ensure the safety of the common bottom special structure test, the common bottom structure is not allowed to bear negative pressure during the entire pressure test cycle, that is, the pressure at the upper end of the common bottom shall not be higher than the pressure at the lower end. The pressure at the upper and lower ends of the common bottom is monitored by real-time monitoring of the pressure measuring device at the rear end of the upper box and the pressure measuring device at the front end of the lower box, and is associated with the emergency discharge device. When the pressure value displayed by the pressure measuring device at the rear end of the upper box is higher than the pressure value displayed by the pressure measuring device at the front end of the lower box, the emergency discharge device of the upper box is opened to relieve the pressure of the upper box until the pressure measuring device at the rear end of the upper box is lower than the pressure measuring device at the front end of the lower box. At the same time, in order to avoid the situation where the pressure value of the pressure measuring device at the rear end of the upper box is higher than the pressure value of the pressure measuring device at the front end of the lower box, a step-by-step alternating small step coordination method is adopted during the filling, pressurization, pressure relief and back discharge processes.

[0024] The present invention also provides a method for performing a pressure deformation test using the above-mentioned thin-wall double-cavity common bottom structure tank pressure test equipment, comprising the following steps:

[0025] 1) Turn the tank from horizontal to vertical and place it on the test base, and connect relevant pipelines and devices (including measuring sensors, exhaust and air supply devices, emergency discharge devices, etc.);

[0026] 2) In order to avoid the influence of the pressure difference between the upper and lower boxes on the common bottom, the filling sequence is first the lower box and then the upper box; because the top of the lower box is a closed structure with a common bottom, the gas in the box cannot be directly discharged. Therefore, when the lower box is filled, the gas in the lower box is discharged through the lower box exhaust / air replenishment device; the lower box is filled from the rear bottom flange. After the lower box is filled, the lower box exhaust / air replenishment device is sealed, and then the lower box is pressurized. The pressure applied is based on the balance of the deadweight pressure of the water column in the upper box; when the upper box is filled, the gas in the upper box is discharged through the upper box exhaust / air replenishment device; the upper box is filled from the side flange of the storage tank and exhausted from the top flange. During the filling process, close attention should be paid to the lower box.

[0027] 3) After filling, the upper and lower boxes are pressurized alternately and coordinated. The pressure of the upper box shall not be higher than that of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure. After pressurizing to the target test pressure, maintain the pressure, and then visually inspect the welds and interface positions of the box body;

[0028] 4) After the pressurization is completed, the upper and lower boxes are alternately coordinated to release the pressure. The pressure of the upper box shall not be higher than the pressure of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure;

[0029] 5) After the pressure relief is completed, the upper and lower boxes are coordinated alternately to recover the test medium. During the pressure relief process, air must be replenished in the box in real time to prevent negative pressure from being generated in the box;

[0030] 6) Remove relevant pipelines and devices, and dry the residual test medium in the tank. After drying, visually inspect all welds on the inner and outer surfaces of the tank to confirm whether there are any defects.

[0031] Preferably, the step 2) comprises the following steps:

[0032] a) Close the upper tank filling and discharge control valve, open the lower tank filling and discharge control valve, connect the lower tank with the filling pipeline, open the lower tank exhaust / air supply device, connect the lower tank with the external atmospheric environment;

[0033] b) During the filling process, the gas in the lower box is discharged through the lower box exhaust / air supply device. Pay attention to monitoring the pressure measuring device at the front end and the rear end of the lower box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure to avoid product overpressure. If the pressure increases, the filling flow rate needs to be adjusted;

[0034] c) When water flows out of the lower tank exhaust / air supply device, stop filling the lower tank and close the lower tank filling and discharge control valve; when water stops flowing out of the lower tank exhaust / air supply device, close the lower tank exhaust / air supply device;

[0035] d) Pressurize the lower box by squeezing water under pressure, and the pressurization pressure is based on the pressure that can offset the deadweight pressure of the water column in the upper box to avoid negative pressure on the bottom;

[0036] e) Open the upper tank filling and discharge control valve to connect the upper tank with the filling pipeline, and open the upper tank exhaust / air supply device to connect the upper tank with the external atmospheric environment;

[0037] f) During the filling process, the gas in the box is discharged through the upper box exhaust / air replenishment device. Pay attention to monitoring the pressure measuring device at the front end of the upper box and the pressure measuring device at the rear end of the upper box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure to avoid product overpressure. If the pressure increases, the filling flow rate needs to be adjusted;

[0038] g) During the filling process of the upper tank, it is necessary to monitor the pressure measuring device at the front end and the rear end of the lower tank. If the lower tank is close to the pressure test pressure, the pressure will be released through the exhaust / air supply device of the lower tank;

[0039] h) When the upper tank is filled to the top of the storage tank, the point liquid level sensor is triggered, filling is stopped, and the upper tank filling and discharge control valve and the upper tank exhaust / air supply device are closed.

[0040] Preferably, step 3) comprises the following steps,

[0041] a) Pressurize the lower box by squeezing water under pressure. After pressurizing to the inspection pressure (generally 0.2MPa), check the plugging cover, pipeline, valve, sensor, and instrument interface connected to the lower box. After confirming that there is no leakage, continue to pressurize;

[0042] b) During the pressurization of the lower box, it is necessary to monitor the pressure measuring devices at the front end and the rear end of the upper box to prevent the upper box from overpressure due to the deformation of the bottom of the lower box during pressurization. If the upper box is close to the pressure test pressure, the pressure will be relieved through the exhaust / air supply device of the upper box;

[0043] c) After pressurizing to the target test pressure of the lower box, maintain the pressure, and then visually inspect the welds and interface positions of the lower box for problems (whether there are cracks, leakage, etc.);

[0044] d) Pressurize the upper box by squeezing water under pressure. After pressurizing to the inspection pressure (generally 0.2MPa), check the plugging cover, pipeline, valve, sensor, and instrument interface connected to the upper box. After confirming that there is no leakage, continue to pressurize;

[0045] e) During the pressurization of the upper box, it is necessary to pay attention to monitoring the pressure measuring devices at the front end and the rear end of the lower box. Since the upper box is pressurized and the bottom is deformed, the pressure of the lower box will increase with the increase of the pressure of the upper box. If the lower box exceeds the pressure test pressure range of ±0.005MPa, the pressure will be relieved through the exhaust / air replenishment device of the lower box. After the pressure is relieved to the lower limit of the test pressure range of ±0.005MPa, the upper box will be pressurized again, and this process will be repeated until the upper box is pressurized to the target assessment pressure;

[0046] f) After pressurizing to the target test pressure of the upper box, maintain the pressure, and then visually inspect the welds and interface positions of the upper box for problems (such as cracks and leaks).

[0047] Preferably, step 4) includes the following steps:

[0048] a) Open the upper tank filling and discharge control valve, and discharge the pressure of the upper tank by slowly returning water through the filling pipeline. When the pressure at the front end of the upper tank is close to 0, open the upper tank exhaust / air supply device to connect the tank with the external atmosphere. When the upper tank is depressurized, close the upper tank filling and discharge control valve;

[0049] b) Open the lower tank filling and discharge control valve, and discharge the pressure of the lower tank by slowly returning water through the filling pipeline. After the pressure at the front end of the lower tank is close to the initial protection pressure, stop the pressure discharge and close the lower tank filling and discharge control valve;

[0050] Step 5) comprises the following steps,

[0051] a) Open the upper tank filling and discharge control valve, and use the water pump to recover the test medium in the upper tank. After the recovery is completed, close the upper tank filling and discharge control valve;

[0052] b) Open the exhaust / air supply device of the lower box to release the residual pressure in the lower box and keep the exhaust / air supply device of the lower box in a normally open state;

[0053] c) Open the lower box filling and discharge control valve, and use a water pump to recover the test medium in the lower box. During the recovery process, air is replenished into the box through the lower box exhaust / air replenishment device. After the recovery is completed, close the lower box filling and discharge control valve.

[0054] After the test is completed, the relevant test pipelines, measuring sensors, exhaust and air supply devices, emergency discharge devices, etc. are removed, and the residual test medium in the tank is dried after the tank is taken off the shelf.

[0055] After drying, all welds on the inner and outer surfaces of the tank are visually inspected to confirm whether there are defects such as cracks and corrosion. Surface defects found during the inspection are scraped and removed. If the thickness is lower than the base thickness of the welding area after removal, repair welding is required, and the pressure test is carried out again after repair welding.

[0056] The present invention also provides a method for measuring volume using the above-mentioned thin-wall double-cavity common bottom structure tank pressure test equipment, comprising the following steps:

[0057] a) Close the upper tank filling and discharge control valve, open the lower tank filling and discharge control valve, connect the lower tank with the filling pipeline, open the lower tank exhaust / air supply device, connect the lower tank with the external atmospheric environment;

[0058] b) Confirm the starting point of filling the lower box through the lower box filling zero level device, and start to accumulate and calculate the mass of the medium flowing into the lower box;

[0059] c) During the filling process, the gas in the lower box is discharged through the lower box exhaust / air supply device. Pay attention to monitoring the pressure measuring device at the front end of the lower box and the pressure measuring device at the rear end of the lower box (the pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure;

[0060] d) When water flows out of the lower tank exhaust / air supply device, stop filling the lower tank, close the lower tank filling and discharge control valve, and record the cumulative mass of the lower tank filling m2; when water no longer flows out of the lower tank exhaust / air supply device, close the lower tank exhaust / air supply device, and record the cumulative mass of the medium discharged by Q2, and subtract it from m2 to get the mass of the medium in the lower tank;

[0061] e) Pressurize the lower box by squeezing water under pressure, and the pressurization pressure is based on the pressure that can offset the deadweight pressure of the water column in the upper box;

[0062] f) Open the upper tank filling and discharge control valve to connect the upper tank with the filling pipeline, and open the upper tank exhaust / air supply device to connect the upper tank with the external atmospheric environment;

[0063] g) Confirm the starting point of the upper tank filling through the upper tank filling zero level device and start to accumulate and calculate the mass of the medium flowing into the upper tank;

[0064] h) During the filling process, the gas in the box is discharged through the upper box exhaust / air replenishment device. Pay attention to monitoring the pressure measuring device at the front end of the upper box and the pressure measuring device at the rear end of the upper box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure;

[0065] i) During the filling process of the upper tank, it is necessary to monitor the pressure measuring device at the front end and the rear end of the lower tank. If the lower tank is close to the pressure test pressure, the pressure will be released through the exhaust / air supply device of the lower tank;

[0066] j) After the upper tank stops filling, close the upper tank filling and discharge control valve and the upper tank exhaust / air supply device, and record the cumulative mass m1 of the upper tank filling; if the tank is not full, add more through the measuring cup and record the added amount, and add it to m1 to get the mass of the medium in the upper tank.

[0067] Compared with the prior art, the pressure test equipment and method for a thin-walled double-cavity common bottom tank described in the present invention have the following advantages:

[0068] (1) The test equipment described in the present invention can realize the pressure test of a large-diameter, thin-walled, double-cavity, common-bottom structure tank. By setting up a pressure measuring device, an exhaust / air supply device, a filling pipeline, etc., it can realize pressure measurement and emergency discharge control, filling and discharge starting and ending points and exhaust / air supply control, common-bottom pressure coordination control, etc., thereby ensuring the safety and reliability of the pressure test of the common-bottom structure tank.

[0069] (2) The test method described in the present invention is based on the public test equipment, and a specific common bottom tank pressure test process implementation method is designed to form a large diameter thin wall double cavity common bottom structure tank distributed coordinated pressure test method.

[0070] (3) The test equipment of the present invention is not only applicable to the pressure test requirements of common bottom storage tanks, but can also meet the pressure test requirements of various tank-type pressure vessels; at the same time, the present invention can also realize the measurement of the volume of common bottom storage tanks. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0072] Figure 1 A simple structural schematic diagram of the test equipment according to an embodiment of the present invention;

[0073] Figure 2 The present invention is a test flow chart of an embodiment of the present invention.

[0074] Description of reference numerals:

[0075] 1. Upper box filling and discharge control valve; 2. Lower box filling and discharge control valve; 3. Upper box exhaust / air supply device; 4. Lower box exhaust / air supply device; 5. Upper box filling and zeroing liquid level device; 6. Lower box filling and zeroing liquid level device; 7. Upper box front end pressure measuring device; 8. Upper box rear end pressure measuring device; 9. Lower box front end pressure measuring device; 10. Lower box rear end pressure measuring device; 11. Upper box emergency discharge device; 12. Lower box emergency discharge device; 13. Exhaust / air supply pipe; 14. Common bottom; 15. Filling pipeline; 16. Point liquid level sensor. DETAILED DESCRIPTION

[0076] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0077] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0078] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0079] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0080] A pressure test equipment for a thin-walled double-cavity common bottom structure tank, comprising a pressure measuring device and a filling pipeline 15;

[0081] The pressure measuring device comprises an upper tank front end pressure measuring device 7 for measuring the highest pressure of the upper tank, an upper tank rear end pressure measuring device 8 for measuring the lowest pressure of the upper tank, a lower tank front end pressure measuring device 9 for measuring the highest pressure of the lower tank, and a lower tank rear end pressure measuring device 10 for measuring the lowest pressure of the lower tank;

[0082] The filling pipeline 15 is divided into two paths, one of which is connected to the filling port of the upper tank of the storage tank, and the pipeline of the path is provided with an upper tank filling and discharge control valve 1; the other is connected to the filling port of the lower tank of the storage tank, and the pipeline of the path is provided with a lower tank filling and discharge control valve 2;

[0083] It also includes an upper box exhaust / air replenishment device 3 connected to the top of the upper box of the storage box and a lower box exhaust / air replenishment device 4 communicated with the lower box of the storage box.

[0084] The filling port of the upper tank is located at the bottom end of the upper tank side of the storage tank, and the upper tank exhaust / air replenishing device 3 is located at the top of the upper tank of the storage tank; the filling port of the lower tank is located at the lower end of the lower tank of the storage tank;

[0085] The upper box front end pressure measuring device 7 is arranged at the top of the upper box of the storage tank, the upper box rear end pressure measuring device 8 is arranged at the bottom of the upper box of the storage tank; the lower box rear end pressure measuring device 10 is arranged at the bottom of the lower box of the storage tank.

[0086] It also includes an exhaust / air supply pipe 13 that can extend to the top of the lower box of the storage tank; the lower box front end pressure measuring device 9 and the lower box exhaust / air supply device 4 are arranged on the exhaust / air supply pipe 13.

[0087] It also includes an upper tank emergency discharge device 11 and a lower tank emergency discharge device 12 connected to the top of the tank; the lower tank emergency discharge device 12 is connected to the exhaust / air supply pipe 13;

[0088] The pipelines connecting the filling pipeline 15 with the upper tank and the lower tank of the storage tank are respectively provided with an upper tank filling and resetting liquid level device 5 and a lower tank filling and resetting liquid level device 6;

[0089] Also included is a point level sensor 16 connected to the top of the tank.

[0090] The upper box front end pressure measuring device 7, the upper box rear end pressure measuring device 8, the lower box front end pressure measuring device 9, and the lower box rear end pressure measuring device 10 are all pressure measuring sensors;

[0091] The upper box exhaust / air supply device 3 and the lower box exhaust / air supply device 4 are exhaust / air supply valves.

[0092] A method for performing a pressure deformation test using the above-mentioned thin-wall double-cavity common bottom structure tank pressure test equipment comprises the following steps:

[0093] 1) Turn the tank from horizontal to vertical and place it on the test base, and connect relevant pipelines and devices (including measuring sensors, exhaust and air supply devices, emergency discharge devices, etc.);

[0094] 2) To avoid the influence of the pressure difference between the upper and lower boxes on the common bottom, the filling is carried out in the order of first the lower box and then the upper box; since the top of the lower box is a closed structure with a common bottom, the gas in the box cannot be directly discharged, and the lower box is filled from the rear bottom flange. When the lower box is filled, the gas in the lower box is discharged through the lower box exhaust / air replenishment device 4. After the lower box is filled, the lower box exhaust / air replenishment device 4 is sealed, and then the lower box is pressurized, and the pressure applied is based on the balance of the deadweight pressure of the water column in the upper box; when the upper box is filled, the gas in the upper box is discharged through the upper box exhaust / air replenishment device 3;

[0095] The specific operations include:

[0096] a) Close the upper tank filling and discharge control valve 1, open the lower tank filling and discharge control valve 2, connect the lower tank with the filling pipeline 15, open the lower tank exhaust / air supply device 4, connect the lower tank with the external atmospheric environment;

[0097] b) confirming the starting point of filling the lower box through the lower box filling zero level device 6, and starting to accumulate and calculate the mass of the medium flowing into the lower box;

[0098] c) During the filling process, the gas in the lower box is discharged through the lower box exhaust / gas replenishment device 4. Pay attention to monitoring the pressure measuring device 9 at the front end of the lower box and the pressure measuring device 10 at the rear end of the lower box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure to avoid product overpressure. If the pressure increases, the filling flow rate needs to be adjusted;

[0099] d) When water flows out of the lower tank exhaust / air supply device 4, stop filling the lower tank, close the lower tank filling and discharge control valve 2, and record the cumulative mass of the lower tank filling m2; when water no longer flows out of the lower tank exhaust / air supply device 4, close the lower tank exhaust / air supply device 4, and record the cumulative mass of the medium discharged by Q2, and subtract it from m2 to obtain the mass of the medium in the lower tank;

[0100] e) pressurizing the lower box by squeezing water under pressure, with the pressurization pressure being based on the pressure that can offset the deadweight pressure of the water column in the upper box, so as to avoid negative pressure on the common bottom 14;

[0101] f) Open the upper tank filling and discharge control valve 1 to connect the upper tank with the filling pipeline 15, and open the upper tank exhaust / air supply device 3 to connect the upper tank with the external atmospheric environment;

[0102] g) confirming the starting point of the upper tank filling through the upper tank filling zero level device 5, and starting to accumulate and calculate the mass of the medium flowing into the upper tank;

[0103] h) During the filling process, the gas in the box is discharged through the upper box exhaust / air replenishment device 3. Pay attention to monitoring the upper box front end pressure measuring device 7 and the upper box rear end pressure measuring device 8. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure to avoid product overpressure. If the pressure increases, the filling flow rate needs to be adjusted;

[0104] i) During the filling process of the upper tank, it is necessary to monitor the pressure measuring device 9 at the front end of the lower tank and the pressure measuring device 10 at the rear end of the lower tank. If the lower tank is close to the pressure test pressure, the lower tank exhaust / air replenishment device 4 will be used to release the pressure to prevent the lower tank from being over-pressurized due to the liquid column pressure of the upper tank;

[0105] j) When the liquid in the upper tank is filled to the top of the storage tank, the point liquid level sensor 16 is triggered. After the upper tank stops filling, the upper tank filling and discharge control valve 1 and the upper tank exhaust / air replenishment device 3 are closed, and the cumulative mass m1 of the upper tank filling is recorded; if the tank is not full, it is supplemented through a measuring cup and the added amount is recorded, and the mass of the medium in the upper tank is obtained by adding it to m1.

[0106] 3) After filling, the upper and lower boxes are pressurized alternately and coordinated. The pressure of the upper box shall not be higher than that of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure. After pressurizing to the target test pressure, maintain the pressure, and then visually inspect the welds and interface positions of the box body;

[0107] The specific operations include the following:

[0108] a) Pressurize the lower box by squeezing water under pressure. After pressurizing to the inspection pressure (generally 0.2Mpa), check the plugging cover, pipeline, valve, sensor, instrument and other interfaces connected to the lower box. After confirming that there is no leakage, continue to pressurize;

[0109] b) During the pressurization of the lower box, it is necessary to monitor the pressure measuring device 7 at the front end of the upper box and the pressure measuring device 8 at the rear end of the upper box. If the upper box is close to the pressure test pressure, the pressure is released through the upper box exhaust / air replenishment device 3 to prevent the upper box from being over-pressurized due to the deformation of the bottom 14 of the lower box during pressurization;

[0110] c) After pressurizing to the target test pressure of the lower box, maintain the pressure, and then visually inspect the welds and interface positions of the lower box for problems (whether there are cracks, leakage, etc.);

[0111] d) Pressurize the upper box by squeezing water under pressure. After pressurizing to the inspection pressure (generally 0.2MPa), check the plugging cover, pipeline, valve, sensor, instrument and other interfaces connected to the upper box. After confirming that there is no leakage, continue to pressurize;

[0112] e) During the pressurization process of the upper box, it is necessary to pay attention to monitoring the pressure measuring device 9 at the front end of the lower box and the pressure measuring device 10 at the rear end of the lower box. If the lower box exceeds the pressure test pressure range of ±0.005MPa, the pressure is released through the lower box exhaust / air replenishment device 4. After the pressure is released to the lower limit of the test pressure range of ±0.005MPa, the upper box is pressurized again, and this process is repeated until the upper box is pressurized to the target test pressure;

[0113] f) After pressurizing to the target test pressure of the upper box, maintain the pressure, and then visually inspect the welds and interface positions of the upper box for problems (such as cracks and leaks).

[0114] 4) After the pressurization is completed, the upper and lower boxes are alternately coordinated to release the pressure. The pressure of the upper box shall not be higher than the pressure of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure;

[0115] The specific operations include:

[0116] a) Slowly open the upper tank filling and discharge control valve 1, and release the pressure of the upper tank by slowly returning water through the filling pipeline 15. When the pressure at the front end of the upper tank is close to 0, open the upper tank exhaust / air supply device 3 to connect the tank with the external atmosphere. After the upper tank is depressurized, close the upper tank filling and discharge control valve 1;

[0117] b) Slowly open the lower tank filling and discharge control valve 2, and discharge the pressure of the lower tank by slowly returning water through the filling pipeline 15. After the pressure at the front end of the lower tank is close to the initial protection pressure, stop the pressure discharge and close the lower tank filling and discharge control valve 2;

[0118] 5) After the pressure relief is completed, the upper and lower boxes are coordinated alternately to recover the test medium. During the pressure relief process, air must be replenished in the box in real time to prevent negative pressure from being generated in the box;

[0119] The specific operations include:

[0120] a) Open the upper tank filling and discharge control valve 1, and use the water pump to recover the test medium in the upper tank. After the recovery is completed, close the upper tank filling and discharge control valve 1;

[0121] b) Open the lower box exhaust / air supply device 4 to release the residual pressure in the lower box, so that the lower box exhaust / air supply device 4 is in a normally open state;

[0122] c) Open the lower box filling and discharge control valve 2, and use a water pump to recover the test medium in the lower box. During the recovery process, air is replenished into the box through the lower box exhaust / air replenishment device 4. After the recovery is completed, close the lower box filling and discharge control valve 2.

[0123] 6) Remove relevant pipelines and devices, and dry the residual test medium in the tank. After drying, visually inspect all welds on the inner and outer surfaces of the tank to confirm whether there are any defects.

[0124] During the filling process of the tank pressure test, the tank volume is measured simultaneously.

[0125] Taking a certain type of 5m diameter common bottom storage tank as an example, hydraulic test and volume measurement were carried out using the test equipment and method. The filling flow rate adopted a gradient filling method of 20t / h (starting) - 200t / h (large flow) - 50t / h (end), and the volumes of the upper and lower tanks were precisely calibrated. The filling time of the upper and lower tanks was about 1h. Then the hydraulic strength test was carried out. The final test pressure of the lower tank was 0.6MPa, and the final test pressure of the upper tank was 0.3MPa. The test task was successfully completed.

[0126] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pressure test equipment for a thin-walled double-cavity common bottom tank, characterized in that: It includes a pressure measuring device and a filling pipeline (15); The pressure measuring device comprises an upper tank front end pressure measuring device (7) for measuring the pressure at the highest point of the upper tank, an upper tank rear end pressure measuring device (8) for measuring the pressure at the lowest point of the upper tank, a lower tank front end pressure measuring device (9) for measuring the pressure at the highest point of the lower tank, and a lower tank rear end pressure measuring device (10) for measuring the pressure at the lowest point of the lower tank; The filling pipeline (15) is divided into two paths, one of which is connected to the filling port of the upper tank of the storage tank, and the pipeline of the path is provided with an upper tank filling and discharge control valve (1); the other of which is connected to the filling port of the lower tank of the storage tank, and the pipeline of the path is provided with a lower tank filling and discharge control valve (2); It also includes an upper box exhaust / air supply device (3) connected to the top of the upper box of the storage box, and a lower box exhaust / air supply device (4) connected to the lower box of the storage box; The filling port of the upper tank is located at the bottom end of the upper tank side of the storage tank, and the upper tank exhaust / air replenishing device (3) is located at the top of the upper tank of the storage tank; the filling port of the lower tank is located at the bottom end of the lower tank of the storage tank; The upper box front end pressure measuring device (7) is arranged at the top end of the upper box of the storage tank, the upper box rear end pressure measuring device (8) is arranged at the bottom end of the upper box of the storage tank; the lower box rear end pressure measuring device (10) is arranged at the bottom end of the lower box of the storage tank; It also includes an exhaust / air supply pipe (13) that can extend to the top of the lower box of the storage tank; a lower box front end pressure measuring device (9) and a lower box exhaust / air supply device (4) are arranged on the exhaust / air supply pipe (13); It also includes an upper tank emergency discharge device (11) and a lower tank emergency discharge device (12) connected to the top of the storage tank; the lower tank emergency discharge device (12) is connected to an exhaust / air supply pipe (13); An upper tank filling zeroing liquid level device (5) and a lower tank filling zeroing liquid level device (6) are respectively provided on the filling pipeline (15) communicating with the upper tank and the lower tank of the storage tank; It also includes a point liquid level sensor (16) connected to the top of the tank.

2. The pressure test equipment for a thin-walled double-cavity common bottom tank according to claim 1 is characterized in that: The upper box front end pressure measuring device (7), the upper box rear end pressure measuring device (8), the lower box front end pressure measuring device (9), and the lower box rear end pressure measuring device (10) are all pressure measuring sensors; The upper box exhaust / air supply device (3) and the lower box exhaust / air supply device (4) are exhaust / air supply valves.

3. A method for conducting a pressure deformation test using the pressure test equipment for a thin-walled double-cavity common bottom structure tank as claimed in any one of claims 1 to 2, characterized in that: The following steps are included: 1) Turn the tank from horizontal to vertical and place it on the test base, and connect relevant pipes and devices; 2) The filling is carried out in the order of first the lower box and then the upper box; when the lower box is filled, the gas in the lower box is discharged through the lower box exhaust / air replenishment device (4); after the lower box is filled, the lower box exhaust / air replenishment device (4) is sealed, and then the lower box is pressurized, and the pressure applied is based on the balance of the deadweight pressure of the water column in the upper box; when the upper box is filled, the gas in the upper box is discharged through the upper box exhaust / air replenishment device (3); 3) After filling is completed, the upper and lower boxes are pressurized alternately and coordinated. The pressure of the upper box shall not be higher than that of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure. During the pressurization of the upper box, the lower box shall release the pressure higher than the target value in real time. After pressurizing to the target test pressure, maintain the pressure, and then visually inspect the welds and interface positions of the box body; 4) After the pressurization is completed, the upper and lower boxes are alternately coordinated to release the pressure. The pressure of the upper box shall not be higher than the pressure of the lower box at any time, and the pressure difference between the upper and lower sides of the common bottom shall not be higher than the single bottom test pressure; 5) After the pressure relief is completed, the upper and lower boxes are coordinated alternately to recover the test medium. During the pressure relief process, air must be replenished in the box in real time to prevent negative pressure from being generated in the box; 6) Remove relevant pipelines and devices, and dry the residual test medium in the tank. After drying, visually inspect all welds on the inner and outer surfaces of the tank to confirm whether there are any defects.

4. The method according to claim 3, characterized in that: The step 2) includes the following steps: a) Close the upper tank filling and discharge control valve (1), open the lower tank filling and discharge control valve (2), connect the lower tank with the filling pipeline (15), open the lower tank exhaust / air supply device (4), connect the lower tank with the external atmospheric environment; b) During the filling process, the gas in the lower box is discharged through the lower box exhaust / air supply device (4). Pay attention to monitoring the pressure measuring device (9) at the front end of the lower box and the pressure measuring device (10) at the rear end of the lower box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure; c) When water flows out of the lower tank exhaust / air supply device (4), stop filling the lower tank and close the lower tank filling and discharge control valve (2); when water stops flowing out of the lower tank exhaust / air supply device (4), close the lower tank exhaust / air supply device (4); d) Pressurize the lower box by squeezing water under pressure, and the pressurization pressure is based on the pressure that can offset the deadweight pressure of the water column in the upper box; e) Open the upper tank filling and discharge control valve (1) to connect the upper tank with the filling pipeline (15), and open the upper tank exhaust / air supply device (3) to connect the upper tank with the external atmospheric environment; f) During the filling process, the gas in the box is discharged through the upper box exhaust / air supply device (3). Pay attention to monitoring the upper box front end pressure measuring device (7) and the upper box rear end pressure measuring device (8). The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure; g) During the filling process of the upper tank, it is necessary to monitor the pressure measuring device (9) at the front end of the lower tank and the pressure measuring device (10) at the rear end of the lower tank. If the lower tank approaches the pressure test pressure, the pressure is released through the lower tank exhaust / air supply device (4); h) When the upper tank is filled to the top of the storage tank, stop filling and close the upper tank filling and discharge control valve (1) and the upper tank exhaust / air supply device (3).

5. The method according to claim 3, characterized in that: Step 3) includes the following steps: a) Pressurize the lower box by squeezing water under pressure. After pressurizing to the inspection pressure, check the plugging cover, pipeline, valve, sensor, and instrument interface connected to the lower box. After confirming that there is no leakage, continue to pressurize; b) During the pressurization of the lower box, it is necessary to monitor the pressure measuring device (7) at the front end of the upper box and the pressure measuring device (8) at the rear end of the upper box. If the upper box approaches the pressure test pressure, the pressure is released through the upper box exhaust / air supply device (3); c) After pressurizing to the target test pressure of the lower box, maintain the pressure, and then visually inspect the weld and interface position of the lower box to see if there are any problems; d) Pressurize the upper box by squeezing water under pressure. After pressurizing to the inspection pressure, check the plugging cover, pipeline, valve, sensor, and instrument interface connected to the upper box. After confirming that there is no leakage, continue to pressurize; e) During the pressurization process of the upper box, it is necessary to monitor the pressure measuring device (9) at the front end of the lower box and the pressure measuring device (10) at the rear end of the lower box. If the pressure of the lower box exceeds the range of ±0.005MPa of the pressure test pressure, the pressure is released through the lower box exhaust / air supply device (4). After the pressure is released to the lower limit of the test pressure range of ±0.005MPa, the upper box is pressurized again. This process is repeated until the upper box is pressurized to the target test pressure. f) After pressurizing to the target test pressure of the upper box, maintain the pressure, and then visually inspect the welds and interface positions of the upper box for problems.

6. The method according to claim 5, characterized in that: Step 4) includes the following steps, a) Open the upper tank filling and discharge control valve (1), and discharge the pressure of the upper tank by slowly returning water through the filling pipeline (15). When the pressure at the front end of the upper tank is close to 0, open the upper tank exhaust / air supply device (3) to connect the tank with the external atmosphere. After the pressure of the upper tank is discharged, close the upper tank filling and discharge control valve (1); b) Open the lower tank filling and discharge control valve (2), and discharge the pressure of the lower tank by slowly returning water through the filling pipeline (15). After the pressure at the front end of the lower tank is close to the initial protection pressure, stop the pressure discharge and close the lower tank filling and discharge control valve (2); Step 5) includes the following steps, a) Open the upper tank filling and discharge control valve (1), and use a water pump to recover the test medium in the upper tank. After the recovery is completed, close the upper tank filling and discharge control valve (1); b) Open the lower box exhaust / air supply device (4) to release the residual pressure in the lower box, so that the lower box exhaust / air supply device (4) is in a normally open state; c) Open the lower box filling and discharge control valve (2), and use a water pump to recover the test medium in the lower box. During the recovery process, air is replenished into the box through the lower box exhaust / air replenishment device (4). After the recovery is completed, close the lower box filling and discharge control valve (2).

7. A method for measuring volume using the pressure test equipment for a thin-walled double-cavity common bottom tank structure as claimed in any one of claims 1 to 2, characterized in that: The following steps are included: a) Close the upper tank filling and discharge control valve (1), open the lower tank filling and discharge control valve (2), connect the lower tank with the filling pipeline (15), open the lower tank exhaust / air supply device (4), connect the lower tank with the external atmospheric environment; b) confirming the starting point of filling the lower tank by the lower tank filling zero level device (6) and starting to accumulate and calculate the mass of the medium flowing into the lower tank; c) During the filling process, the gas in the lower box is discharged through the lower box exhaust / air supply device (4). Pay attention to monitoring the pressure measuring device (9) at the front end of the lower box and the pressure measuring device (10) at the rear end of the lower box. The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure. d) When water flows out of the lower tank exhaust / air supply device (4), stop filling the lower tank, close the lower tank filling and discharge control valve (2), and record the cumulative mass of the lower tank filling m2; when water no longer flows out of the lower tank exhaust / air supply device (4), close the lower tank exhaust / air supply device (4), and record the cumulative mass of the medium discharged by Q2, and subtract it from m2 to obtain the mass of the medium in the lower tank; e) Pressurize the lower box by squeezing water under pressure, and the pressurization pressure is based on the pressure that can offset the deadweight pressure of the water column in the upper box; f) Open the upper tank filling and discharge control valve (1) to connect the upper tank with the filling pipeline (15), and open the upper tank exhaust / air supply device (3) to connect the upper tank with the external atmospheric environment; g) Confirm the starting point of filling the upper tank through the upper tank filling zero level device (5) and start to accumulate and calculate the mass of the medium flowing into the upper tank; h) During the filling process, the gas in the box is discharged through the upper box exhaust / air supply device (3). Pay attention to monitoring the upper box front end pressure measuring device (7) and the upper box rear end pressure measuring device (8). The pressure is strictly prohibited to exceed 1 / 2 of the product pressure test pressure; i) During the filling process of the upper tank, it is necessary to monitor the pressure measuring device (9) at the front end of the lower tank and the pressure measuring device (10) at the rear end of the lower tank. If the lower tank approaches the pressure test pressure, the pressure is released through the lower tank exhaust / air supply device (4); j) After the upper tank stops filling, close the upper tank filling and discharge control valve (1) and the upper tank exhaust / air supply device (3), and record the cumulative mass m1 of the upper tank filling; if the tank is not full, add more through a measuring cup and record the added amount, and add it to m1 to get the mass of the medium in the upper tank.

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